''Acentria'' is a

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispec ...

moth Moths are a paraphyletic group of insects that includes all members of the order Lepidoptera that are not butterflies, with moths making up the vast majority of the order. There are thought to be approximately 160,000 species of moth, many of w ...

genus of the family

Crambidae The Crambidae are the grass moth family of lepidopterans. They are variable in appearance, the nominal subfamily Crambinae (grass moths) taking up closely folded postures on grass stems where they are inconspicuous, while other subfamilies includ ...

described by

James Francis Stephens James Francis Stephens (16 September 1792 – 22 December 1852) was an English entomologist and naturalist. He is known for his 12 volume ''Illustrations of British Entomology'' (1846) and the ''Manual of British Beetles'' (1839). Early li ...

in 1829. Its only species, ''Acentria ephemerella'', the watermilfoil moth or water veneer, was described by

Michael Denis Johann Nepomuk Cosmas Michael Denis, also: ''Sined the Bard'', (27 September 1729 – 29 September 1800) was an Austrian Catholic priest and Jesuit, who is best known as a poet, bibliographer, and lepidopterist. Life Denis was born at Schärding ...

and

Ignaz Schiffermüller Ignaz Schiffermüller (born 2 October 1727 in Hellmonsödt; died 21 June 1806 in Linz) was an Austrian naturalist mainly interested in Lepidoptera. Schiffermüller was a teacher at the Theresianum College in Vienna. His collection was presented ...

in 1775. It is used as an agent of

biological pest control Biological control or biocontrol is a method of controlling pests, such as insects, mites, weeds, and plant diseases, using other organisms. It relies on predation, parasitism, herbivory, or other natural mechanisms, but typically also invo ...

against the noxious

aquatic plant Aquatic plants are plants that have adapted to living in aquatic environments (saltwater or freshwater). They are also referred to as hydrophytes or macrophytes to distinguish them from algae and other microphytes. A macrophyte is a plant that ...

known as

Eurasian watermilfoil ''Myriophyllum spicatum'' (Eurasian watermilfoil or spiked water-milfoil) is native to Europe, Asia, and north Africa, but has a wide geographic and climatic distribution among some 57 countries, extending from northern Canada to South Africa. It ...

(''Myriophyllum spicatum''). Acentria ephemerella 3

The adult male is a white moth with a wingspan of about 12 millimeters. There are two female morphologies. Most females are flightless and live on the surface of the water or just submersed. A few females have longer wings and fly. This is an

aquatic insect Aquatic insects or water insects live some portion of their life cycle in the water. They feed in the same ways as other insects. Some ''diving'' insects, such as predatory diving beetles, can hunt for food underwater where land-living insects c ...

; most of its life cycle takes place in the water. The female is fertilized at the surface and dives to lay egg masses on aquatic plants, such as watermilfoil. The

larva A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. The ...

emerges and bores into the stem of the plant, gluing together plant material to create a shelter. It

girdles A belt, especially if a cord or rope, is called a girdle if it is worn as part of Christian liturgical vestments, or in certain historical, literary or sports contexts. Girdles are used to close a cassock in Christian denominations, including ...

stems as it feeds, which causes significant damage to the plant as stems and leaves die or break off. The larva

pupa A pupa ( la, pupa, "doll"; plural: ''pupae'') is the life stage of some insects undergoing transformation between immature and mature stages. Insects that go through a pupal stage are holometabolous: they go through four distinct stages in their ...

tes inside an underwater cocoon filled with air. Upon emergence, males and flighted females swim to the water surface and fly away. This moth is used as a biocontrol agent on watermilfoil, but carefully, because it lacks host specificity and will attack other plant species, including natives. It tends to prefer ''M. spicatum'' over other plants. This is a European moth, but it was found in Canada in the 1920s, having been probably introduced accidentally. It is established in much of the northeastern United States, where it appears to have the ability to reduce watermilfoil infestations.

References

* Coombs, E. M., et al., Eds. (2004). ''Biological Control of Invasive Plants in the United States''. Corvallis: Oregon State University Press, 171.

External links

Cornell Species Profile

Acentropinae Monotypic moth genera Biological pest control insects Moths of Europe Moths of North America Taxa named by James Francis Stephens Crambidae genera {{Acentropinae-stub